What landmark is associated with the T4-5 vertebrae?

The sternal angle, also known as the angle of Louis, is located at the level of the T4-5 vertebrae. This anatomical landmark can be palpated as the prominence where the manubrium meets the body of the sternum. It serves as a critical reference point in the thorax, helping to delineate various structures and levels of the rib cage.

In addition to being at the level of the T4-5 vertebrae, the sternal angle is significant in clinical practice as it marks the approximate level of the second rib, which is important for counting ribs during physical examinations or imaging studies. This anatomical relationship is vital for healthcare professionals in assessing cardiovascular and respiratory health.